Multiple spindle vertical crankshaft lathe



April- Z5, w39. w. F. GROENE Er A1.. 72,156,153

MULTIPLE SPINDLE VERTICAL CRANKSHAFT LATHE i Filed April 8, 1957 13sheets-sheet 1 INVENTORS w\LL\F\M EGROEN:

Hmmm J. sKMmN wmv-:Ie Ie METER ATTORNEY.

April 25, i939. w. F. GROENE ET AL 23%53 MULTIPLE SPINDLE VERTICALCRANKSHAFT LATHE l Filed April 8, 1937 15 sheets-sheet 4:a

INVENTORS WILLIAM F. GROENE HAROLD J. slEKMgNN BY WALTER a. MeeaATTORNEY.

Apri 25, 1939. w. F. GROENE ren'y AL 2,156,153

MULTIPLE SPINDLE VERTICAL CRANKSHAFT LATHE Filed April 8, 1937 l5Sheets-Sheet 5 INVENTORS lLLum Fwoene HAROLD .n.snsKMmm wam-esa RMETER vBYNMMM Q ATTORNEY .April 25, 1939, w. F. GROENE ET Al. 2,156,153

MULTIPLE SPINDLE VERTICAL CRANKSHYAFT LATHE Filed April 8, 1937 13sh'ets-sheet 4 sTATmN FOUR INVENTORS mmm Ecmoene v HAROLD J.$\EKMANNWALTER R-METER l 15u/@MCM 95mg ATTORNEY.

lApr 25, i939. w., F. GROENE T -AL MULTIPLE SPINDLE VERTICAL CRANKSHAFTLATHE Filed April 8, 1937 13 Sheets-Sheet 5 BY @1MM Apnl 25,1939. w. F.GROENE Er AL 2,156,153

l-ULTIPLE SIINDLE VERTICAL CRANKSHAPT LATHE Filed April 8. 1937 13sheets-sheet e 138 i 151 u y e1 -1 15an I? il 151i FIGNII INVENTORS muumEssonne nanou .smkmm BY m wagens u METeg i ATTORNEY.

13 Sheets-Sheet 7 W. F. GROENE ET AL MULTIPLE SPINDLE VERTICALCRANKSHAFT LATHE Filed April 8, 1937 1 n m um K. 0 5 d lfm. m Il DIApril 25, 1939.

INVENTORS MHLURM F. GROENE HAROLD J. $\E\ MP\NN w ALTER M v ATTORNEYApril 25, 1939. y w. F. GROENE ET Al. v 2,155,353 MULTIPLE SPINDLEVERTICAL CRANKSHAFT LATHE r Filed April 8, i937 13 shets-sheet 'sINVENTORS WILLIAM F. GROENE HARoLn .LsleKMNw WALTER RMETER pri 25, W39.w. F. GROENE ET AL 2,56153 MULTIPLE SPINDLE VERTICAL CRANKSHAFT LATHEFiled April 8, 1937 13 sheets-Sheet 9 INVENTORS WlLLJAM F- GROENE HAROLDJ. S\EKMRNN ATTORNEY.

April 25, 1939 w. F. GROENE ET Al. 2,156,153

MULTIPLE SPINDLE VERTICAL GRANKSHAFT LATHE Filed April B, 1937 13Sheets-Sheet i0 Iii) 1l 1' l INVENTORS wxLLum F. caRoENe maken J. sKMANNBY WALTER R. METER mwm.

ATTORNEY.

April 25, 1939. w. F. GROENE ET AL 2,156,153

MULTIPLE SP1NDLE VERTICAL CRANKSHAFT LATHE Filed April 8, 1957 13Sheets-Sheet 1l E INVENTORS WLUAM F. GROENE HARoLn J. S\E\ MANH WAL-yeaRMETER Fi y BY' ATTORNEY.

April 25, 1939. F. GROENE ET AL MULTIPLE SPINDLE VERTICAL CRANKSHAFTLTHE 13 shetS-sheet l2 Filed April 8, 1937 I.... i imi zwww INVENTORSWILUM P GROEN ATTORNEY.`

HAROLD J. SEKMANN WAL ER K-ME MMM nida April 25, 1939.

w. F. GROENE ET Al.

' MULTIPLE SPINDLE VERTICAL CRANKSHAFT LATHE Filed Ap'ril a, 1937 1:5Sheets-sheet 13 rm mmm im 3m Ilvi, m5 rom Nm. mom :um Mdm .oonvm m5 EJEELLE 56E n En E r E 2h En En own 5m am 3m n own d :n Y E x5 m2. E3?,zorrmkm :2.5km zoFFrm u .u MOM 2m\ En 3m L 3m @E 5m En n m3 8m Ill 5mmmm INVENTORS wlLLmM F. GROENE HRRGL'D J.5\EKMNN BY WALTER RMETERATTORNEYt Patented Apr. 2 5, 1939 UNITED ISTATES PATENT OFFICE MULTIPLESPINDLE VERTICAL oaANx- SHAFT LA'rnn 52 Claims.

This invention pertains to multiple spindle crankshaft lathes, moreparticularly to crankshaft lathes of a character adapted to machiningthe line bearings and associated portionsvof crankshafts.

Our invention consists in certain new and useful improvements,modifications, and additions to multiple spindle lathes of-a characterset forth in the copending application of William F.

Groene and Walter R. MeyerpSerial Number An object of our invention isto provide in a Y lathe a series of vertically arranged center driveWork spindles mounted on an indexing carrier in which spindlescrankshafts may be chucked and rotated and successively presented to aseries of work stations at which cutting tools are applied to thecrankshafts to progressively machine the line bearings and associatedsurfaces thereof.

Another object is to provide in a lathe a series of work spindles,mounted on an indexing carrier, which are each driven 'by an independentsource of power.

Another object is toeprovide in a lathe a series of work spindles,mounted on an indexing carrier, which are at all times rotating underlpower, except at the loading or unloading station, at predeterminedvdifferent rates of speed foreach work station. l

Another object is to provide in a lathe a series of `work spindlesmounted on an indexing carrier, some of said spindles being operable atpredetermined diiferent rates of speed While all of said spindlesmaintain rotation except when at the loading and unloading station.

, Application April s, 1937 semi No. 135,740

positing them in an appropriate chamber under the base of the machineior quick and'easy removal.

Another feature is to arrange the cutting tool holders at the variouswork stations so that they 5 may be readily moved from cutting positionaway from the work for access to the cutting tools.

' A further feature isto provide al combined motor, frequency changer,and coolant pump V for operating the lathe. l

Other objects and features of our invention will appear from thefollowing detailed description of the drawings in which: Figure I is afront elevation of the machine particularly showing the loading stationand the u loading and unloading devices associated therewith.

Figure 1I is a view, partly in section on line II--II of Figures I, III,IV, V, and XVI.

Figure III is a plan view of the top of the ma- 20 .chine particularlyshowing the tool feeding mechanism.

Figure IV is a. plan view, partly in section on line IV-IV of Figure II,particularly showing the indexing carrier, the work spindles, andassociated work stations. v

Figure V is a plan view, partly in section on line V-V of Figures II,XIV, and XV, particularly showing the indexing carrier, and associatedindexing mechanism. y l

Figure VI is an elevation, partly in section on line VI-VI of Figure IIIparticularly showing the turning tools of work station one.

Figure VII is an elevation, partly in section on line VII- VII of FigureIII, particularly showing the forming tools of workv station two.

Figure VIII is a plan view partly in section on line VIII-VIII oi FigureVII, partly broken away to more clearly show the means for feeding andadjusting the forming tools relative to the work.

Figure 1X is a plan view partly in section on une Dr-Ix of Figure VI.

Figure X is an elevation of one of the loading and unloading devicesassociated 'with .the loading station. 45

Another object is to provide in a lathe a series (ff Figure XI is a viewpartly in section on line of work spindles mounted on an indexingcarrier some of said spindles being operable at predetermined difierentrates of speed while others of said spindles are operable at variablerates of speed.

XI--XI of Figure X.

Elgure XII is a view partly in section` on the line XII-XII of FigureXIII.

Figure XIII is a view partly in section on the line XIII-XIII of FigureX. i l

Figure XIV is an enlarged view of a portion of Figure VII to moreclearly show the indexing mechanism lfor the indexing carrier.

Figure XVis an enlarged view partly inv section on the line II-II ofFigures I, III, IV, and V particularly showing the chip receivingcompartment under the base of the machine and the combined motor,frequency changer, and coolant Pump.

'Figure XVI is a view partly in section on line XVI-XVI of .Figures Iand l1 showing the differential drive mechanism for feeding and rapidtraversing the cutting tools.

Figure XVII shows a crankshaft at the loading station. f

Figure XVIII shows the application oi.' turning tools to a crankshaft atwork stationone.

Figure XIX shows the application of forming tools to a crankshaftat workstation two. Figure XX shows the application of forming tools to acrankshaft at work station three.

Figure XXI shows the application of forming tools to a crankshaft atwork station four. Figure XXII shows the application of turning tools toa crankshaft at work station five.

Figure XXIII shows the application of forming tools to a crankshaft atwork station six.

Figure XXIV shows the application of .turning tools to a crankshaft atwork station seven.

' Indexing carrier The machine has a circular base upon which isrotatably mounted the indexing carrier 2 journaledabout the bearingportion 3 of the upstanding central` boss 4 of the base I and supportedon an appropriate anti-friction thrust bearing 5 mounted on the base I.Note Figures I, II, III, JIV, V, and Fixed to the boss 4 by suitablescrews y6 is the central column 1. Mounted on appropriate pads 8 spacedaround the periphery of the base 'I, Figure V, is a'series of toolholder frames 9 and I0, Figure IV. An upper housing Il is xed to thecolumn 1 by bolts I2 and is also supported on the upper ends of theframes 9 and |0 and securely fixed thereto by appropriate' means to givethe necessary rigidity to said frames.

Power for operating the mechanism for indexing the carrier 2 is derivedfrom the electric motor I3 mounted on the bracket I4` fixed to thehousing I I by the bolts I5, Figure III. 'Ihe motor pinion I6 of themotor I3 drives the gear I1 fixed on the drive shaft I8 Journaled in theanti-fric- 'tion bearings |9 and 20 in the column 1. Fixed to the lowerend of the shaft I8, Figure XIV, is the pinion 2| which drives the gear22 of the compound gear 22-23 journaled on the stud 24 fixed in the baseI. The gear 23 of the compound gear 22-23 drives the indexing gear 25which is fixed to the shaft 26 journaled on anti-friction bearings 21and 28 in the base I. On the stud 29 xed in the gear 25 is mounted aroller 30 which is adapted to nicely nt in the indexing slots 3| Aformedby the segmentary pieces 32 fixed'y to the underside 33 of the indexingcarrier 2 by the screws 34, Figure V. On each of the pieces 32 is formedan arcuate boss 35 having a concave,

.surface 36 which is nicely engaged by the convex surface 31 of anarcuate boss 38 formed on the gear 25 when said carrier is in an indexedposition. .It can thus be seen that upon rotation of the gear 25 byenergizing the motor I3 the roller 30 ,(Figure V) will be moved into aslot 3| at which instant the surfaces 36 and 31 of the arcuate bosses 35and 38 become disengaged. Continued rotation of the gear 25 moves theroller 30 which is entered in a slot 3| so as to cause rotation of thecarrier 2 from one indexed position to the next indexed position. Justas theroller 30 again leaves the slot 3| the surfaces 36 and 31 againreengage and remain so during a substantial gportion of the rotationofthe gear 25, the purpose of the engagement of said surfaces 6 and 31being to bring the carrier to substantially accurate indexed positionwithout requiring the motor I3 to be accurately stopped to accomplishthis result.` f

Means are provided to brngthe carrier 2 into precise indexed positionafter it is approximately indexed by the surfaces 36 and 31 of theancuate bosses 35 and 38, comprising an indexing plunger 39 axiallysl'idable in A bushings 40 and 4| fixed in the base which has a taperedend portion 42 which is normally urged into engagement with a matingtapered bore of the indexing bushings 43 xed in the carrier 2 by meansof an appropriately mounted spring 44. A lever 45, pivotally mounted ona stud 46 in the bracket 41 fixed on the base I, has a rounded endportion 40 fitted in an appropriate transverse slot 49 in the plunger 39and a roller 56 mounted thereon which is engaged by a cam surface 5| onthe gear 25. The cam surface 5i is so arranged on the gear 25 that uponrotation of the gear the plunger will be held withdrawn during the timethe roller 30 is moving the carrier 2 and the` surfaces 36 and 31 aredisengaged and to permit engagement of the plunger 39 in the bush 43byspring 4d when the surfaces 36 and 31 are engaged and the roller 30ineffective to move the carrier.`

` Fluid pressure operated clamping mechanism is annular surface 41a ofthe base I thus securelyI holding the carrier 2 on the base I againstrelative lrotation whenin indexed position.

Center drive work spindles On the indexing carrier 2 is mounted a seriesof pedesls 52 upon which are mounted the center' drive chuck housings53, Figures II, IV, and HV, which carry the center drive ring gears 54suitably journaled on anti-friction bearings 55. 'I'he ring gears 54,two for each work spindle as shown. inthis exemplary disclosure, eachhave chucking devices 56 for gripping a crankshaft C in a mannerpreferably as shown in Patents Re. 19,905, Re. 20,090, or 2,030,020.

Means are provided for properly axially positioning the crankshaft Cinsaid chucking devices 56 comprising a center pin 51, Figure XIV,axially slideable in bushing 58 fixed inthe pedestal 52. The lower endof the center pin 51 has an inclined concave surface 59 adapted to abutagainst the inclinedI convex surface 60 on the plunger 6I axiallyVslideable in the bore 62 in the pedestal 52, the structure of surfaces59 and 66 being such as to prevent rotation of thecenter pin 59 uponrotation of the crank shaft C. The center pin 51 may be moved axiallyupward by moving the plunger 6I radially toward thecenter of rotation ofthe carrier 2 by rotating the screw 63 rotatably mounted against axialmovement in the bracket 64 fixed to the pedestal 52, which screw 63 isappropriately threaded in the nut 65 fixed in the plunger 5| The centerpin 51 may be returned axially downward by withdrawing the plunger 6|radially outward of the carrier 2 aided by gravity and the weight of thecrankshaft C when unclamped in the chucking` devices 58.

A hand-wheel 66 mounted on the rotatable and axially slideable shaft 81in the bracket 88 fixed to the base I at the loading station providesman.. ual means for rotating screw 63 by moving the shaft 81 axially toengage the socket end 88 over the flatted endv portion 10 of the screw63 and rotating the hand wheel 66. Aspring 1| appropriately mounted inthe bracket 88 serves to automatically disengage the socket end 68 andportion 10 of the screw 53 when the hand wheel 86 is .released toprevent damage to the lathe upon indexing of the carrier 2.

'Ihe ring gears 54 for each work spindle are driven from a motor 12,Figures II and IV, mount ed on the bracket 13 by bolts 14 which bracket18 in turn is fixed on the center drive chuck housing 53. The motorpinion 15 drives the gear 15 xed on the shaft 11 journaled onanti-friction bearings 18 and 19 in the housing v53. Fixed on the shaft11 is a pinion l80 adapted'to drive the gear. 8| xed on the shaft 82journaled on antifriction bearings 83 in housing 53. Fixed on the shaft82 are like pinions 84 which drive the like' gear portions 85 of thering gears 54 whereby said ring gears for each work spindle may berotated in synchronism' by the motor 12.`

One method of energizing the motors 12 is to provide a frequency changer86, Figure XV, driven by a constant speed motor 81. "The frequencychanger 86 is electrically connected by appropriate wiring to the taps88, Figure II, of the collector rings 89 xed to and surrounding thevcolumn 1. Oneach ofthe driving motors 12 is mounted a suitable brushcarrier 90 properly holding the current collecting-brushes 8| in contactwith the collector rings '89 so that power .may be delivered from thefrequency changer 86 to the motors 12.

Noting Figure IV, the collector rings 89 com. prise a series of segments1S, SI, S27 S3, S4, S5, S6, and S1, which are attached to suitableinsulating material 82 mounted on the column 1 and separated byinsulating-portions 93 forming part of the contact lsurface of thecollector rings 89. The segment LS is normally de-energized except whendynamically braking for accurate stopping or inching a Work spindle attheloading station to facilitate manipulation of the chucking devices56. y

One form of operation is to have all of the segments Si to S1,inclusive, connected' to the frequency changer 88 whereb all of saidmotors may be continuously opera except when the brushes 9| arecontacting the normally de-energized segment for the work spindle in theloading station. Passage of the brushes 9| across the insulatingportions 93 during indexing is so rapid asto preclude any appreciableslowing down of the motors 12 and work spindles. Various differentfrequencies may be simultaneously selected for all the segments SI toYS1, inclusive,l from the frequency changez-$6 in the usualman- I ner ofselecting the proper poles 'of the frequency i 3 be provided for thework spindles at the work stations. For example, segments 8|, Si, and S1of motors 12 and their associated work spindles when at the respectivework stations one, five,

and seven; segment S2 may be so energized as to cause the work spindlesat Vwork station two to rotate'less rapidly; and segments S3, S4, and S8may be so energized as to cause the work spindles at work stationsthree, four, and ve to rotate relatively slowly; By this arrangementproper may be so energized as to cause rapid rotation spindle speeds maybe automatically provided. for

each type of machining operation undertaken at each work station by theindexing of the carrier 2.

Still another arrangement would be to havecertain of the segments, asforinstance the segment S2, supplied from a source of power which wouldcause armotor 12 connectedthereto to operate at variable rates of speedcontrolled by thel movement of the tool feeding devices associated withsaid station, 'for example in a manner fully set forth in the co-pendingapplication of Wil- Tool feeding mechanism Power for actuating the toolfeeding mechanism is derived from the feed drive motor 94 and thereversible rapid traverse drive motor mounted on the upper housingFigure III. Both of said motors are-connected to a difierential gearingparticularly shown in Figures II and XVI. The feed drive motor 94 has apinion- 96 adapted to drive the gear 81 xed on the worm shaft 88 whichvis-suitably journaied in the dierential gear case 99. A worm^|00 formedon the shaft 88 is adapted to drive the worm wheel 0| suitably mountedon the differential cage,.|02 journaled in appropriate anti-frictionbearings |03 and Midii in the gear case 98. The motor 94 is operatedduring the forward move-- ment of the cutting tools to the work duringwhich time the motor @t relatively slowly rotates the worm wheel |0| andcage |02. n the motor 94 is stopped the cage is held agains .rotation bythe locking effect of the worm |00 and worm wheel |0| combination whichalso prevents the cage |02 from being rotated at a speed different fromthe speed at which it is being rotated by the motor 84. Y.

The reversible rapid traverse motor has a pinion |05 which driyes thegear |06 fixed on the shaftA |01 journaled on the anti-friction bearings|08 and |09 in the gear case99 and f in the gear case 98 and in the bore||`8 of the cage |02. 0n thesplined end portion |20 of the shaft ||6 is`mounted the bevel gear |2| alsoy adapted to engage the bevel pinions,||3 and ||4. Associated with the reversible rapid traverse motor 95 is asolenoid operated brake |22 for rapidstopping of said motor when rapidtraversing the tools to or from the work.` The brake v|22 furtherservesto assureno'n-rotation of the traverse motor 95 when the tools arebeing actuated in feeding motion by motor 94.

When rapid ltraverse is desired in either di.- rect'ion the motor 95 isoperatedin either direction to cause the shaft |01 to be rotated atrelatively high speed. In instances where the feed drive motor is notoperating during rapid traverse,.the cage |02 will be held stationary,the bevel gear H2 which is rotated by shaft |01 will rotate the bevelpinions 3 and |44 on pin ||5, whichpnions in turn will cause rotation ofbevel gear |2| and its shaft I I6 at -the same speed as the shaft |01,`but in reverse direction, to thereby cause rapid rotation of shaft H6for rapid traverse purposes.

In instances where the feed motor 94 is 'operating during rapidtraverse, there will 'be a slight increase or decrease in the rapidtraverse speed of shaft ||6 relative to shaft |01 by the addition orsubtraction of the speed of rotationl of the cage |02 caused by the feedmotor. However, because of the relatively slow speed of rotation of thecage |02 no appreciable eii'ect on the proper functioning of the rapidtraverse speed will result so that the feed and rapid traverse motorsmay be operated either simultaneously or independently without damage tothe lathe mechanism or its proper operation.

When it is desired to cause feeding for the cutting tools of the lathe,the shaft 31 and the bevel gear H2 are held from rotation by applyingthe brake |22 to prevent rotation of the motor 95. The cage 802, beingrotated slowly by the motor 90, carries the bevel pinions H3 and H4 onthe pin H5 about the bevel .gear ||2 thereby' causing said pinions H3and H4 to revolvefonthe pin H5 which motion in turn causes the pinionsto drive the bevel gear |2| and the shaft at relatively slow speed forfeeding purposes. Y

Power from the shaftldt is'transmitted by the pinion |23 formed on theshaft il@ which drives the gear |20 fixed on the shaft |25 journaled onanti-friction bearings |26 and |21 in 45 the gear case 99. On the shaft|25 is fixed the bevel pinion |28 which drives the bevel gear |29 fixedon the vertical shaft |30 journaled in the bearing |3| in the bracket|32 fixed to upper housing and in the bearing |33 in said housingFormed' on the shaft |30 adjacent the bearing |33 is a pinion |34 whichdrivingly engages the segmental interna-l gear |35 formed on the arcuatecam plate slide |36 whereby said slide may be rapidly moved by motor 95or slowly moved by motor 94 in the arcuate guideways |31, |38, and |39in the housingv At some of the work stations turning tool actuatingmechanism is provided for feeding cutting tools longitudinally of theaxis of spindle rotation. At other Work stations forming tool actuatingmechanism is provided for feeding cutting tools perpendicular to theaxis of spin- `dle rotation.

In this particular -exemplary embodiment, in which the lathe is shownapplied to machining crankshafts, the work stations one, five, and

seven are arranged for turning operations', Figures III, IV, V'I, IX,XVIII, XXII,y and XXIV. A

description of the tool actuating mechanism of o work station one willsuice also for stations |44 for the roller |46 mounted on the stud 4 6xed in the axially movable rod |41. A bracket |48 secured to the housingby bolts |49 has a. half bearing |50 to properly steady the upper end ofthe rod |41 with its roller properlyv engaged between the cams |42 and|43, the bracket |48 also serving to maintain the slide |36 in theguideways |31, |38, and |39. The rod |41 is further guided for axialmovement in the bushing |5| flxed in the housing and -projecting in theslot |5|a in the slide |36, and in bushings |52, |53, |54 and |55 in theframe 9. Securely clamped to the rod |41 by suitable means |56 are thetool holder supports |51 and |58 which carry the respective tool holders|59 and |80 for the turning tools'` |6I, |62, |63, |64, and |65. Byloosening the clampingmeans |56 the tool holder supports |51 and |58 maybe swung aboutthe rod |41` through a substantial arc thus bringing thecutting Itools away from cutting position for convenience in checkingand replacing said tools. -1

In order to maintain 4the Atool'holder support in proper cuttingposition for the tools, a hardcned shoe |66 is secured to the support|51, Figure IX, by screws -|61 which abuts against andis free to slidealong a hardened strip |68 in a slot |10 formed in the frame 9 has aprojecting end surface |1| which lightly engages the surface |12 of theshoe |66 when the wingnut |13 threaded on the stud |14 fixed in clamp|69 is tightened against the surface |15 of the` frame 9 to therebymaintain the tool holder support |51 in proper cutting position. Thestud |14 passes through the slot |16 so' that upon vloosening theWingnut |13 and sliding the stud |14 and clamp |69 in slot |10 to theleft, Figure IX, the tool holder support |51, when the clamping-means|56 is loosened, may be swung from cutting position for access to thetools.

'I'he work stations two, three, four, and six arefarranged for formingoperations, Figures III, IV, VII, Vm, XIX, XX, )CII and Xml. Adescription of the tool actuating mechanism of work station two willsuffice also for stations three, four, and six as the mechanism issubstantially the same for all forming stations. Fixed to the cam plateslide |36 is the cam plate |11 by screws |18 to which are fastened thecams.|19 and |80 which form an appropriate cam slot |8| for the roller|82 carried on the stud '|83 fixed to the outer end of the lever arm|84. The lever arm |84 is free to swung through a substantial arc in theslot |85 of the slide |36,

the lever arm |84 having a hub portion |86 securly fixed to the upperend |81 of the rock shaft |88 by a pin |89.

The rock shaft |88, journaledin bearings |90, |9|, |92, |93, |94, and|95 in theframe |0, has a series of integral pinions |96, |91, and |98formed thereon. Forming tool holder supports |99, 200, and 20| arepivotally mounted on bearlsecured tothe frame 9. A clamp |69 mountedings 202, 203, and 204 about the rock shaft |00.A

adjacent vthe respective associated pinions |96, |91, and |98, wherebythe tool holder supports rmay be swung to or from cutting position foror out of a slot 201 in the frame I0 and having a wing-nut 208 threadedthereon which may be tightened down against the surfaceV 209' of theframe |'to securely hold the surfaces 2I0 oi' the support 200 in iirmcontact with the surface 2|| of the Aframe I0. By loosening thelwing-nut 208 and swinging the eye bolt 205 cnt of the slot 201 the toolholder support 200 may be swung from cutting position for access to thetools.

The forming tools 2|2, 2|3, 2|4, 2|5, 2|6, and 2|1, .Figures VII `andVIII, are appropriately mounted on the respective tool holders 2|8, 2|9,220 slideably mounted in the respective tool holder supports |99, 206,and 20|. Mounted in suitable recesses 22| in the tool holders 2|0, 2|9,and 220 are the respective racks 222, 223, and 224 which are drivinglyengaged bythe respective pinions |96|91, and |98.

The racks may be adjusted longitudinally of the tool holders andmaintained in such adjusted position by means of the hollow screw 225threaded in the tool holders through which passes a bolt 2-26 threadedin the racks, particularly shown in Figure VIII. By slightly backing-onthe bolt 226 and rotating the hollow screw 225 the rack 223 may beadjusted relative to the tool holder 2|9 thereby providing means forsetting each tool holder independently for properly 'positioning thecutting tools relative to the work C without effecting the position ofthe rock shaft |83 and its associated mechanism. 'Ilghteningthe bolt 226locks the screw 225'andrack 223 in adjusted position.

It is thus apparent from the above description that by operating themotors 94 and 35 in proper sequence the arcuate cam plate slide |36 canbe slowly or rapidly moved in its arcuate guideways |31, |38 and |39 tomove the turning station cams |4 and |43 for axially moving shaft |41fory actuating turning tools and the forming Station cams |19 and |80 torock the shaft |86 for actuating the forming tools in feed or rapidtraverse movements.

Work loading and unloading4 mechanism Associated with the loadingstation is a pair of loading and unloading cranes 221 and 228 eachcapable. of loading and unloading work vertically into and out of thecenter drive work spindles. Usually in the operation of the lathe cranecomprises a vertical-cylinder 229 xed at its lower end in a bracket 230on upright supports 23| and 232, by suitable bolts 238, which supportsare appropriately vfastened to the base and upper housing of the lathe.A piston 234 reciprocatable in the cylinder 229 is fastened on thepiston rod 235 by a suitable pin 236, the rod 235 being supported forboth axial and rotary movement in conventional. 'packing glands231and238 at each end of the cylinder 229. On the gland 231 is mounted athrust bearing 239 which supports the swinging reelhousing 240. Thepiston rod 235 passes into the bore 24| in the reel housing 240 and hasconnected to its upper end the rack bar 242 also axially slideable inthe bore 24|, the rack .bar 242 having its upper end passing through thebore 243 in the bracket-244 xed on vthe upper housing by screws 245toglvel ,added support tothe upper end of the crane. v.

On the shaft 246 xeg'l in the reel housing 24| by pin 241 is..,rotatablymounted thepinion 243, which is driven by the rack 243 formed on therack bar 242, having an integral flanged portion 2501110 which issecured the cable reel 25| by bolts 2 52.- 'I'he lifting cable'253 isattached t0 the reel 25| and passes over and downward from the pulley254 rotatably mounted on the stud 255 xed in the reel housing 240 andhas connected to its outer e`r1d the work gripping device 256.

Fluid pressure from the pump 40a may be directed to either cylinderchamber 251 -or 2,58 of the cylinder ,229 through lines 229a and 229|),Figure XI for raisingor lowering the piston 234 and its associated rod235 by properly manipulating the lever 259 of the control valve 260. It

can be seen that when uid pressure is Vapplied in chamber 251 the rod-2'35 will be moved downward and cause the cable 253 to wind up on thereel 25| thereby raising the work gripping device 256 and that whenfluid pressure is applied in chamber 258 the rod 235 will be raisedcausing the cable 25| to unwind from the reel 25| and lower the workgripping device 256.

The piston rod 235 projects downwardly beyond the gland 238 and has itsouter end steadied in a bracket 26| fastened to the upright 2li or 232.The downward movement of the rod 235 is limited by the surface 262 ofthe piston 234 striking the surface 263 of the bracket 238 'thusbringing the work gripping device 256 to proper up` position forswinging the cranes' in. the paths 221a and 228:1, with work C supportedthereon, to or from the work spindle in the loading station. i

When the crane is swung outward from the work spindle to be loaded thedownward position oi the work gripping device is -limited by the surface264 of the piston 234 striking the surface 265 of the body portion 266'of the gland 231 thereby permitting the work gripping device 256 totravel suillciently far downward. to pick up workv of! o! the operationoor 293.

Q When the crane is swung inward over the work spindle to be loaded thedownward travel of work gripping device is limited bythe dog 261 xed onthe rod 235 which strikes the plunger 268 or the control valve 260tripping the valve to neutral position. The dog 261 is so arranged as toautomatically cause the work held in the gripping device 256 to `bedeposited in .proper axial position for chucking in the center drivechucklng devices. A cutaway portion 269 ren.- ders the dog 261ineii'ective when the crane is swung outward from the work spindle.

'I'he structure of the work gripping device 256, particularly shown inFigures XII and IUII, comprises a. socket 210 having a suitableconnection 21| with the cable 253. The yoke 212 has a stem 213 whichslidably fits in the bore 214 in the lower end of the socket 210 and issupsocket 210 to limit travel of the washer in theboren216. A spring 280bearing against the surface 28| 0f the Socket 210 and the surface 282 Ufthe washer 21s supports the Ayam: 212 and au weight imposed thereon thepurpose of which is to permit limited axial movement of the yokerelative to the cable v253 when finally .positioning work in the workspindle.

on the yoke zu 1s formed an ,intesmins n having serrated jaws 234carried therein which contact the end, as forrexample the stub-'fend 285oi the crankshaft C. A movable eccentric ser- Coolant supply and chipdisposal Referring particularly to Figures II, V, and

. XV, the coolant supply 29| for the cutting tools at the work spindlesof the lathe is maintained in the combined coolant reservoir and chipcompartment 292 provided in the operating floor 293 and partly under thebase of the lathe. The

coolant 29| is pumped from the compartment 292 to the cutting tools bythe coolant pump'294 which is dri/ven by the 'motor 81 which drives thefrequency changer 86.

The coolant 29| fromlthe cutting tools carries the chips 295 downwardlyto the inclined surface 296 of the pedestals 52 from which the chips arewashed by the coolant into the annular chip and coolant trough 291formed in the base One or more chip Scrapers 298 fixed to the indexinglcarrier 2 travel around in the trough 291 upon indexing of the carrieran'dconduct the chips, deposited in the trough from the various workspindles, to the discharge opening 299 of the trough 291, through whichthe chips 295 drop into the compartment 292. A screen 300 in thecompartment 292 strains the chips from contact with the coolant-pump 294and provides a suitable inclined surface up` which the chips 295 may bescrapedrwhen the recess doors are opened.

Machining mtliod lThe method of machining work piecesfas for example theline bearings and associated surfaces of crankshafts, is particularlyshown in v.

Figures XVII to XXIV, inclusive. Figure XVII shows a crankshaft C at theloading station showing the rough surface 302 which is ma.-`

associated cheeks 3|0, 3H, 3|2, and 3|3 of th line bearings 303, 304,and 305.

The crankshaft C is indexed from the loading station to station one,Figure XVIII, at which tool -|6| nish turns aportion of the stub end 285to accurate dimension; tool |62 rough turns a portion 3|5 of the stubeniig285; tool |63 nish "turns the portion\3|6 of the line bearing 303;tool |64 rough turns a portion 3|1 surrounding the oil groove 309; andtoot |65 rough turns the outside diameter 3|8 of the flange 308. Duringthe above machining operations the work spindle at station one isrotated at relatively high speed for e ciency 'in the turning operationshere underta en. At station two, Figure formlng tol 2|2 -finish facesthe cheekf3l0; tool 2|3 finish faces the cheek 3| I; tool 2 |4 finishfaces 'the cheek 3|2; and tool 2 I5 finish faces the cheek 3|3, all ofsaid tools machining down to the outside diameter of the respectivefillets 3|9, 320, 32|, and 322. 'I'he tool 2|8 rough faces the insideface 323 of the flanges 308; and the tool 2|1 rough faces the outside.face 324 of the flange 308. The work 15 spindle at this station two isoperated at variable speed in order to maintain constant cutting speed Yof the forming or facing tools on the Work sur- Y faces being heremachined.

At station three, Figure XX, tool 325 faces the end 326 of the stub end285; tool 321 rough forms the portion 328 on the gear fit 301; tool 329rough forms the portion V330 on the line bearing 303; tool 33| roughforms the portion 332 and tool 333 rough forms the portion 334 on theline bearing 304;.tool 335 rough forms the portion 336 and tool 331rough forms the portion 338 on the line bearing 305; tool 339 roughforms the portion 340 of the oil groove 309', and ltool 34| finishchamfers the portion 342 on the flange 308. The work spindle at thisstation three is operated at relative slow speed for elimination ofchatter in` the forming operations.

At station four, Figure XXI, tool 343 rough forms the portion 344 of thegear flt 301; bool 345 rough forms the portion 346 of the llet 3|9; tool341 rough forms the portion 348 of the llet 320; tool 349 rough formsthe portion 350 of the fillet 32|; tool 35| rough forms the portion 352of the fillet 322; tool 353 rough forms the portion 354 adjacent the oilgroove 309; and the tool 355 finish forms the oil groove 3 09. Spindlerotation at this station is at a relatively slow rate for these formingoperations.

At station flve, Figure XXII, the` tool 358 finish turns an additionalamount of vthe stub end portion 3|4 beginning at position 356a; tool 351turns f an additional amount -of the portion 3|5 on the gear fit 301beginning at position 351a; tool 358 rough turnsan additional amount 302of the portion 330 of the line bearing 303 beginning at position 358a;tool 359 rough turns the portion 302 of the line bearing 304 between the`portions 332J and 334 beginning at position 859:1; tool 360 rough turnsthe portion- 302 of thev line bearing 305 between the portions`336 and338 beginning at position 36011; the tool 36| Jturns off the oil slinger362 adjacent the oil groove309; and the tool 363 finish turns thediameter of the flange 308." Relatively rapid spindle rotation isutilized at this station.

At station six, Figure XXIII, the tool 364 cham-v fers the stub end 285;the tool 365 finish forms the fillet 366 between the stub end 285 andgear fit A301; the tool 361 finish forms the fillet and chamfers theline bearing 303 adjacent the gear fit 301; the tool 368 finish formsthe fillet 3|9 of line bearing 303; the tools 369 and 310 nish form thefillets 320 and 32| oi' the line bearing 304;the

tools 31| and 312 nnish forms the fillet azz and the portion 354 of theune bearing aus; and the tools 313 and 314 nish the faces of the flange308. Relatively slow spindle speed is used for `this spindle.

At station seven, the final work station, Figure l XXIV, the tools 315,316, and 311 beginning at the respective positions 315a, 316a, and 311afinish turn the remaining rough turned portions ofl the respective linebearings 303, 304, and 305; and the tool 318 finish turns th outsidediameter of the oil groove 309 adjacent the flange 308.

It can thus be seen`that this lathe is adapted to progressively machinea series oi.' work pieces or crankshaftsA at a series of work stationsat which the spindles may be rotated at the same, different, or variablerates of speed at the various work stations during machining operations.

AThe machine is also adapted to simultaneously partially rough andpartially finish machine work said distributing means for applyingelectrical arcaica Having fully set forth and described our invention,what we claim as new and desire to secure by United States LettersPatent ls:

1. In a multiple spindle machine tool, a base, a rotatable carriermember mounted on said base, a plurality of vertically arranged centerdrive work spindles each comprising at least one center drive ring chuckand at least one center mounted on said member, tool means and a loadingstation associated with said work spindles, means mounted on said basefor axially adjusting the center of a work spindle at said loadingstation, and means for rotating said carrier member and rotating saidwork spindles.

2. In a multiple spindle machine tool, a rotatable carrier member, aplurality of work spindles mounted on said member each comprising acenter drive ring gear chucking device, an electric driving motor, andtransmission mechanism connecting said motor to said ring gear wherebysaid chucking device may be rotated, and means for rotating said carriermember.

3. In a multiple spindle machine tool, a rotatable carrier member, aplurality of work spindles mounted on said member each comprising aplurality of center drive ring gear chucking deyices, an electricdriving motor,` and transmission mechanism connecting said motor to saidring gears whereby said chucking devices may be rotated in synchronism,and means for rotating said carrier member.

'4.- In a multiple spindle machine tool, a rotata' ble carrier member, aplurality of Work spindles mounted on said member each comprising arotatable work "holder and an electric motor for rotating said workholder, means for rotating said motors of said Work spindles insynchronism comprising a source of constant frequency electrical energyand means for distributing said energy to all of said motors, and 'meansfor rotating said carrier member.

5. In a multiple spindle machine tool, a ro tatable carrier member aplurality of -work spindles mounted on said member each comprising a.rotatable work holder and an electric motor for rotating said motors oflsaid work spindles at predetermined diiferent speeds comprising asource of electrical energy having predetermined different frequenciesand means for distributing said frequencies to said motors, and meansfor rotating said carrier member.

6. In a multiple spindle machine tool, a rotatable carrier member, aplurality of work spindles mounted on said member each comprising arotatable work holder and an electric motor for rotating said workholder, tool means and a loading station associated with said spindles,means for rotating said carrier member, a source of electrical energy,means for distributing said energy to said motors for rotating saidspindles whereby said energy is automatically cut off from said motor ofa work spindle at said loading station as said carrier member isrotated, and means independent of energy to said motor of said workspindle at the loading station for arresting rotation of or inching saidspindle at the work station.

7. In a multiple spindle lathe, an indexing carrier member, a pluralityof work spindles mounted on said member each comprising a rotatable workholder and van electric motor for rotating said work holder, a series ofwork stations associated with said spindles, means for .indexing saidcardierent speeds, and means for distributing said energy to said motorsto cause the motors to rotate the spindles at the 'work stations at apredetermied speed for each work station.

8. In a multiplevspindle lathe, an indexing carfrier member, a pluralityof work spindles mounted on said member each comprising a rotatable workholder and an'electric motor for rotating said work holder, a. series ofwork stations associated with said spindles, means for indexing saidcarrier, a source of electrical energy adapted to operate said motors ata plurality of predetermined different speeds, and means operable by theindexing of said carrierA member for distributing said energy to saidmotors to cause the'motors to rotate the spindles at the work stationsat a predetermined speed for each work station.

9. In a multiple spindle lathe, a frame, an indexing carrier rotatablymounted on said frame, means for indexing said carrier, a plurality ofwork spindles mounted on said mem` ber each comprising a rotatable Workholder and an electric motor for rotating said work holder, a series ofwork stations and a loading station associated with said spindles, asource of electrical energy adapted to operate said motors, and meansfor distributing said energy to said motors comprising collector ringsmounted on said frame consisting'of a series of independentlyenergizable segments at least one for each work station and said loadingstation, means connecting said source of energy to said segments, andcollecting means associated with each work spindle and cooperating withsaid collector rings to convey said energy to said motors.

10. In a multiple Aspindle lathe, a frame, an

indexing carrier rotatably mounted on said frame, Y

means for indein'ng said carrier, a plurality of worlr spindles mountedo n said member each comprising a rotatable work holder, a series ofwork stations associated with said spindles, a source of electricalenergy consisting of a frequency changer from which may be obtained aplurality of electric currents of different frequencies, means fordistributing said energy to said motors comprising collector ringsmounted on said frame consisting of a series of independentlyenergizable 'segments at least `one for each work station, collectingmeans associated with each work spindle and cooperating with saidcollector rings to convey energy to said motors, and means connectingsaid electric currents of different frequencies to said segments wherebyeach spindle may be rotated at predetermined speeds lfor each workstation.

11. In a multiple spindle lathe, a frame, an

indexing carrier rotatablymounted on said frame, means for indexing saidcarrier, a plurality of work spindles mounted on said member eachcomprising a rotatable work holder, aseries of work stations associatedwith said spindles, a source of electrical energy capable of operatingsaid motors at a plurality of predetermined different speeds, a sourceof 'electrical energy capable of operating said motorsat variablespeeds, means for distributing said )energy to said motors comprisingcollector rings mounted on said frame consisting of a' series ofindependently energizable segments at least' one for each work station,collecting means associated with each work spindle and cooperating withsaid collector rings to convey energy tosaid motors, and meansconnecting said sources'of electrical energy to said segments wherebysaid spindles may be rotated at predetermined different speeds at someof said work sta-

